Decisions, decisions (rebuild or transplant)

[Christien]

So it looks like my engine is ready for the big R. Not positive, but all signs point to it. I just want to get a compression/leakdown to confirm it. All along I've said that rather than rebuild I'd transplant for more power. But I was talking to a guy at a local shop who suggested that for roughly the same price as a complete 3.0, he could rebuild my 2.4T, bore it out to a long stroke 2.5 and with Webers or PMOs (currently has Zeniths) could reasonably expect to see 225hp, which would be more than a stock 3.0. The added plus here is that I get a fresh engine, and it's still the original engine to the chassis. While I'm not overly concerned about originality, that is indeed a plus.

Ballpark estimate from him was $8-9K, parts and labour (including a set of used, presumably rebuild, Webers), whereas a 3.0 swap would be $7-8K, parts and labour. Bear in mind, he's never seen the car, this is all just over the phone.

So my questions:

1. Does it seem reasonable to obtain that kind of power from this type of rebuild? (I'm just quoting what he said - I don't really understand the process of it)

2. Does that price range seem reasonable? (factor in that this is Canada, and everything is 10% or so more expensive than in the US)

3. If 1 and 2 are yes, is this something I could do myself? I realize that's kind of a dumb question, but I mean is it feasible? I rebuilt my 915 last winter, which was difficult, but not outside my abilities, though it did raise the bar of my abilities. I had a few frustrating moments, particularly the big 27mm nut, which took 3 days, 4 helpers in 2 cities and countless tools and bottles of propane to finally crack - things like that really take the fun out of those kinds of projects.

Thanks for any thoughts!

Chris

[304065]

Chris,

Long stroke ST 2,5 is 86.7 x 70.4, 2493cc. That implies an overbore to your cast-iron cylinders from 84mm to 86.7mm, which is more than usually recommended (85 is the recommended limit). Also, one wouldn't typically use cast iron cylinders for a performance application as they don't conduct heat as well as Aluminum. What you really would want are a set of Mahle Nikasil (unobtainium in ST size) or Nickies with custom JE pistons. So that is a key assumption about the quote, new P&C's included or not? Just boring to 85 gets you to 2396cc.

As far as power goes, the Factory got 270 hp from that engine with MFI, so it's techinically achieveable. 225 is about 90 BHP per liter, which is a pretty high specific output if you consider that the 67S through Carrera RS were about 80 BHP/liter. But probably achievable given the right build sheet.

I think his estimates are low, if you add up the parts to be replaced and factor in case work (extensive) and other goodies like twin plug. I would budget between $11K-$15K.

[Christien]

Thanks John - I appreciate your detail. He did mention JE Pistons - I forgot to include that in my initial post, and the cost of those was included in his estimate. He didn't mention anything about the cylinders, but I'd have to assume he'd know if they need replacing too. He's a fairly reputable local guy AFAIK, though I'd of course look into this more deeply as well.

[euro911sc]

You may be getting a 'recession' price. If he can back his price with a specific build sheet post it here and we will tear it apart... if you can get it for fixed cost it sounds good to me on the initial pass.

-Michael

[OldTee]

Ah, the petard. Get a fixed price quote and who knows where the corners are cut. 10k miles down the road you get a nice Oops! Even a transplant has risks. If you want more power buy a newer car. In the long run there is no free lunch.

[Christien]

Originally Posted by OldTee

If you want more power buy a newer car. In the long run there is no free lunch.

Well, I'm not exactly looking for a free lunch, unless $9000 is your definition of pocket change - it's certainly not mine. I don't particularly *want* a newer car - I like my 72. If I have to rebuild the engine, why not go for more power while I'm doing so? Seems like a no-brainer to me. It has to countless race teams for decades, too.

[BK911]

I’ve always been an advocate for shelving the original case (engine if possible) and building up another engine, especially now that the long hoods are approaching collectable status. So in my opinion your decision is simple; shelve the original engine and transplant a 3.x.

[Rich76_911s]

I think the estimate to put the 3.0L into your car is a bit high, but maybe that is just me. For 8K I would want a recently rebuilt warrantied 3.0L engine. Going price seems to be in the 4500 to 5500 range for a typical 3.0L engine pulled out of a car without much documentation and no warranty. And installing a 3.0L into a car shouldn't cost 2500.

If I were you and I was going to swap engines I'd go with a 1978 or 79 3.0L, put carburetors on it, a cam that works well with the carbs, all combined with the exhaust system off your 2.4. It would still appear original and it would go like stink. And I think you could get it done for somewhere in the 7 to 9K range. The tough part would be finding a GOOD replacement 3.0L.

If I were on the hunt for a good 3.0L candidate I'd look for an engine with:
1. Already replaced headstuds
2. Updated Carerra Chain Tensioners
3. Good compression and leakdown numbers. Ideally for this test the engine would still be in the car and running. (Contact some shops and see if they have any customers doing an engine swap)
4. Documents showing it was well cared for.

You'll pay more for it, but the peace of mind is worth the trouble.

If you can rebuild a transmission I am confident that you'll be able to swap a 3.0L into your car.

If I was going to have my engine rebuilt I think I'd spend the $$ on shipping and send it to one of the guys that posts on here a lot. Henry Schmidt, Steve Wenier, TRE, etc. It will cost a little more, but if you decide to sell your car anytime soon having a receipt showing one of those guys built your engine will help resale value significantly. I also think you would get a more accurate estimate from them too. Not one that could change from 7000 to 12000.

[calling911]

Originally Posted by Christien

Well, I'm not exactly looking for a free lunch, unless $9000 is your definition of pocket change - it's certainly not mine. I don't particularly *want* a newer car - I like my 72. If I have to rebuild the engine, why not go for more power while I'm doing so? Seems like a no-brainer to me. It has to countless race teams for decades, too.

There is only one way to get a perfect motor. Do it yourself. I trust NO ONE anymore.. the economy BEGS for short cuts. You can buy an engine stand and all tools you need for WAY less than the labor involved. Find a VERY NICE OWNER OF A MACHINE SHOP and chat with him.. make sure he is a nice guy and PAYS ATTENTION TO DETAILS.. when you ask him a question make sure he listened and responded to your question.. otherwise, you are going to tell him to slice no more than X off of the heads or whatever and he is going to throw it to his wolves and they will just hack it up..

This happened to a friend of mine on a BMW diesel head.. BMW specically says DO NOT cut the head.. the gaskets are HUGE and make up for warpage... what do you think he got back? JUNK.. too high compression for a diesel JUNK.. and he PAID for the junk..

Anyway.. I highly suggest you do it yourself.. if need by buy some storage and put all your garage stuff in it to make room for a nice work area.. cleanliness is critical when re-assembling..

EDIT: and for goodness sake keep your 72!!
Guys will be dieing to help you here especially if you take lots of photos as you go.

I know, time is maybe the issue for you.. if so.. well.. find a known good air cooled builder..

If somehow you can build it yourself it will be a life long experience if you havent done it before.. I have lots of fond memories.. I once built a Nascar V8 for my scca GT1 car.. what an experience that was.. it was all about my machinist.. he held my hand all the way..

[67rebuild]

Christien,

If you don't mind ... who is the 'local guy' I could be looking for a rebuild quote myself...

[Christien]

Don't mind at all - it was Brent at Hunter Motorsports. I don't have the number handy, but it should be easy to find.

[67rebuild]

Thanks ... I have his number .... I was going to have him rebuild my Trany. Just wondering if there were was some shop in the area that I didn't know about.

[Christien]

I know Mantis can also rebuild trannies - they offerred to do mine, but I ended up doing it myself. I did enjoy it and would like to do my engine if I can find the time.

[67rebuild]

I got Auto Select in Newmarket to rebuild mine ... Old school with the original alignment tools and jiggs, cool stuff. Franz is a great guy. He's been around Porsche's since the beginning.

[Dynamohum]

Its a great experience to build your own motor, providing you have lots of time and a warm place to do the work. I'm in the process of doing mine, pulled the engine and disassembled it a few months back when it was much warmer and even then it was a pain working in a cold garage. So I keep sneaking them into the house every chance I get.

Good luck to you, Paul

[Dynamohum]

Forgot to mention torches are a must, I used them on every exhaust nut so as not to snap the studs and on several seized tin mounting bolts. I was very thankful to have them.